Hayden and Hilary Duff. Hilary was asked recently if she ever thought that she could have ended up like Britney Spears or the rest of wild girls her age:

"I don’t look at them and think “that could have been me” because I’m me and I’m not like that. But you never know why that is. I know that it can be really hard and there’s lots of pressure with everyone watching you. But I don’t think that excuses some behaviour.”

What happens here is that Hilary was smart and used condoms and Brit... well, I don't think she knows why those are for yet.